Hoven



wG. HOLST AND E. OOSTERHUIS.

RECTIFIER FOR ALIERNATING CURBENTS.

APPLICATION FILED MAY I0. 1920.

1,410,062. Patented Mar; 21, 1922.

5mm jaw/ Q f a'nmm QwJ W MOW UNITED STATES PATENT- OFFICE.

GILLES HOLST AND EKKO oosrmmms, or smnnovmr, NETHERLANDS, Assmnom T0 NAAMLOOZE vmmoowscrmr PHILIPS omnnlmrmnnmnn, or EIND- HOVEN, NETHERLANDS, A LIMITED LIABILITY oomrm 0F NETHERLANDS.

RECTIFIER FOR ALTEBNATING CUBRENTS.

Specification of Letters Patent. Patented Mar. 21, 1922 Application filed May 10, 1920. Serial ms. 380,238.

T 0 all whom it may concern:

Be it known that we, GILLES Hons'r and EKiro Oos'rsnnurs, subjects of the Queen of the Netherlands, residing at Eindhoven, in the Province of North Brabant, in the Kingdom of the Netherlands, have invented certain new and useful Improvements in or Belating to Rectifiers for Alternating Currents, of which the following is a specification,

For rectifying alternating currents, discharging tubes can be used in which one of the electrodes is brought to a high temperature and it then acts as a cathode. Generally the said cathode is constructed as an incandescent filament, whilst the anode or anodes are usually constructed in the form of a sheet or a rod.

This invention relates to an apparatus of this type in which however, the electrodes are so constructed that they can be used successively either as incandescent cathodes or as anodes, whilst an electrode, which is no longer fit for use as a cathode, can then be used as an anode.

This construction has the advantage, that the life of the apparatus is considerably increased. In case the incandescent filament is burnt out, one of the other electrodes is used for this purpose, whilst the defective incandescent filament can be used as an anode.

The invention is illustrated in the accom panying drawing.

The drawing shows a rectifier for threephase current. The rectifier consists of a discharging tube (1) in which four spirals (2) of tun en or other suitable material are used. ne of the spirals' is brought to mcandescence. The three others are used as anodes. If the'first spiral burntout, one

of the others can ,actas the cathodeand this can be repeated until none of the four spirals is any longer fit for use.

What we claim is:

1. A discharging tube rectifier for alternating currents, having a plurality of elec 1 trodes, each comprising a' conductor for an electric current, whereby it may be rendered incandescent so as to serve as a cathde, while another of said electrodes serves as an anode, and each of said electrodes being adapted, when burned out, to serve as an abode, while another vof said electrodes serves as a-cathode. I

'2. A discharging tube rectifier for alternating currents, having a plurality of electrodes, each comprising a conductor for an electric current, whereby it may be rendered incandescent so as to,serve as a cathode, while other of said electrodes serve as anodes, and each of said electrodes being ada ted, when burned out, toserve as an 

